The present invention relates to fireplaces and, in particular, to gas fired fireplaces, whether free standing or constructed as an insert, and a fireplace boiler.
A variety of primary and supplemental boiler heat sources have been developed over the years to accommodate a variety of fuel types. Most boiler systems are relegated to utility rooms, where they remain unseen. Some outdoor, wood fueled boilers, such as manufactured by applicant, are camouflaged in housings having the appearance of small utility sheds.
A variety of fireplace boilers and retrofit assemblies, which accommodate conventional brick fireplace constructions, have also been developed. A fireplace boiler provides the aesthetic benefits of an open fire combined with the practical ability to transfer heat energy to a larger area by circulating a liquid media through a conduit system.
Most fireplace boilers are constructed to accommodate wood and coal fuels. A variety of retrofit grate assemblies, which include conduits that support a boiler liquid, are particularly known. The grates support the wood and coal fuels. The generated heat is conducted through the walls of the heat exchanger to a contained liquid that, in turn, is conducted through conduits routed about the premises. Some exemplary grate assemblies can be found at U.S. Pat. Nos. 4,046,320; 4,131,231; 4,159,801; 4,159,802; 4,180,053; 4,159,802; 4,335,703; 4,355,625; and 4,473,061.
Some fireplace assemblies conduct heated gases within the hearth area to contact a remotely mounted heat exchanger. U.S. Pat. No. 4,453,532 discloses one such assembly. A transparent door screen assembly of the latter type is also shown at U.S. Pat. No. 4,137,896.
Other fireplace assemblies are known which include liquid conduits in the walls of the firebox. Two of such assemblies, which are intended for use with wood and coal, are shown at U.S. Pat. Nos. 4,271,816 and 4,584,987.
A variety of gas fired fireplaces are also known which distribute a decorative gas fired flame around artificial logs supported to an included grate. These fireplaces tend to be designed principally for aesthetics and not as an efficient heat source. They also frequently induce uncomfortable drafts. Some of these assemblies are shown at U.S. Pat. Nos. 5,584,680; 5,429,495; 5,392,763; 5,320,086; 5,114,336; 5,052,370; 5,081,981; 5,016,613; and 4,976,253.
The present invention was developed to provide a high efficiency gas fired fireplace. The fireplace is constructed to provide a contemporary external appearance and a glass front which optimally exposes the flame, without creating uncomfortable drafts. Heated combustion gasses are directed through a convoluted flow path which starts at a fresh air supply conduit at the chimney and terminates at an exhaust conduit at the chimney. Heat within the gasses is collected at a liquid heat exchanger and distributed through liquid conduits routed about the premises.